---
id: "CVE-2026-91437"
kind: "vulnerability"
aliases: ["CVE-2026-91437"]
title: "Oracle Siebel CRM: network flaw lets privileged user change critical data"
severity: "high"
cvss: 8.7
epss: 0.00361
exploited: false
status: "open"
category: "vendor"
products: [{"name": "Siebel CRM Deployment", "fixed": ["see Oracle CPU Oct 2026 (a release after 26.9; 26.10 per Armis, unconfirmed)"], "affected": ">= 17.0, <= 26.9", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["oracle", "self-hosted", "siebel-crm", "vendor"]
not_affected_if: ["managed-hosting", "versions-outside-17.0-26.9"]
published_at: "2026-10-20T22:20:47+00:00"
first_seen_at: "2026-10-23T21:57:26+00:00"
updated_at: "2026-10-25T12:38:52+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91437", "first_seen_at": "2026-10-23T21:57:26+00:00"}, {"source": "analyst", "url": null, "first_seen_at": "2026-10-23T23:55:08+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-91437", "first_seen_at": "2026-10-25T12:38:52+00:00"}]
---

# Oracle Siebel CRM: network flaw lets privileged user change critical data

Oracle Siebel CRM Deployment server infrastructure has a flaw reachable over HTTP that lets an attacker with high privileges read and modify data. The CVSS vector also marks a scope change, so impact can extend beyond Siebel CRM itself.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Siebel CRM Deployment affected >= 17.0, <= 26.9 fixed see Oracle CPU Oct 2026 (a release after 26.9; 26.10 per Armis, unconfirmed)

## How to check

Check your Siebel CRM Deployment version: 17.0 through 26.9 is affected. Check who holds high-privileged (admin) accounts that can reach the Siebel Server Infrastructure HTTP interface, and whether that interface is reachable from untrusted networks. Confirm in My Oracle Support whether the Oct 2026 CPU Siebel patch is applied.

## Fix

Apply the Siebel CRM patch from Oracle's October 2026 CPU through My Oracle Support (the fixed version is probably a release after 26.9, unconfirmed). Until patched, restrict network access to the Siebel Server Infrastructure HTTP interface to trusted admin hosts and audit privileged accounts. Needs a high-privileged account, so exposure is lower than for unauthenticated sibling CVEs.

## Timeline

- 2026-10-23T21:57:26+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91437
- 2026-10-23T23:55:08+00:00 analyst — Oracle CPU Oct 2026 (Oct 20) is the primary source; Oracle CNA text via Rapid7/CVE.org: Siebel CRM Deployment 17.0-26.9, Server Infrastructure, CVSS 8.7 (PR:H, S:C), VulDB CWE-285. I did not read Oracle's Siebel matrix row, so the fixed version is unconfirmed. Armis says a release after 26.9 and gives 26.10 for a sibling CVE. No KEV, no PoC, no exploitation found. Social posts not searched. Sibling CVEs 91442, 91440 and 91424 hit the same component.
- 2026-10-25T12:38:52+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-91437

## Documents

- [advisory] Oracle Critical Patch Update Advisory - October 2026 https://www.oracle.com/security-alerts/cpuoct2026.html
- [describes] Rapid7: CVE-2026-91437 (Oracle CNA text) https://www.rapid7.com/db/vulnerabilities/cve-2026-91437/
- [mentions] Armis: CVE-2026-91437 https://cve.armis.com/CVE-2026-91437

## From the sources

Vulnerability in the Siebel CRM Deployment product of Oracle Siebel CRM (component: Server Infrastructure).  Supported versions that are affected are 17.0-26.9. Easily exploitable vulnerability allows high privileged attacker with network access via HTTP to compromise Siebel CRM Deployment.  While the vulnerability is in Siebel CRM Deployment, attacks may significantly impact additional products (scope change).  Successful attacks of this vulnerability can result in  unauthorized creation, deletion or modification access to critical data or all Siebel CRM Deployment accessible data as well as  unauthorized access to critical data or complete access to all Siebel CRM Deployment accessible data. CVSS 3.1 Base Score 8.7 (Confidentiality and Integrity impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N).

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_